A. Kirchhoff's Law BNewton's Law of Cooling represents how fast heat diffuses through a material. A....

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A. Kirchhoff's Law BNewton's Law of Cooling represents how fast heat diffuses through a material. A. Thermal Conductivity B. Conductivity A. Radiation given temperature and wavelength are equal. D. Stephan-Boltzmann Law C. Fourier's Law C. Diffusivity C. Thermal Radiation is the rate at which energy is released per unit area (W/m). B. Surface Emissive Power PART 2-PROBLEM SOLVING INSTRUCTION: Answer the following problem, show your solution. (10 pts each) Thermal Diffusivity Emissive Power 1. A thick-walled tube of stainless steel [18% Cr, 8% Ni, k = 19 W/m C] with 2-cm inner diameter (ID) and 4-cm outer diameter (OD) is covered with a 3-cm layer of asbestos insulation (k = 0.2 W/m. C). If the inside wall temperature of the pipe is maintained at 600C, calculate the heat loss per meter length. Also calculate the tube insulation interface temperature. = m.C 59600 Stainless steel T-600C Asbestos T-100C = 2. A steel pipe with 5-cm OD is covered with a 6.4-mm asbestos insulation [k = 0.096 Btu/h ft. F] followed by a 2.5-cm layer of fiberglass insulation [k = 0.028 Btu/h ft F]. The pipe-wall temperature is 315-C, and the outside insulation temperature is 38-C. Calculate the interface temperature between the asbestos and fiberglass. 3. Suppose a 3-in schedule 80 pipe (d, 2.9 in, do = 3.5 in, k = 43) is covered with 1 in of an insulation having k- 60 pr W/m C and the outside of the insulation is exposed to an environment haying h=10 W/m. C and Too=20-C. The temperature of the inside of the pipe is 250C. For unit length of the pipe calculate (a) overall thermal resistance and (b) heat loss. 4. Two long cylinders 8.0 and 3.0 cm in diameter are completely surrounded by a medium with k = 1.4 W/m C. The distance between centers is 10 cm, and the cylinders are maintained at 200C and 35C. Calculate the heat transfer rate per unit length. 5. Find u(x, y) (assume 2D heat transfer, steady state). . 2 0 TEX sin 0 2 sin vin u(x,y) un ha 0 A. Kirchhoff's Law BNewton's Law of Cooling represents how fast heat diffuses through a material. A. Thermal Conductivity B. Conductivity A. Radiation given temperature and wavelength are equal. D. Stephan-Boltzmann Law C. Fourier's Law C. Diffusivity C. Thermal Radiation is the rate at which energy is released per unit area (W/m). B. Surface Emissive Power PART 2-PROBLEM SOLVING INSTRUCTION: Answer the following problem, show your solution. (10 pts each) Thermal Diffusivity Emissive Power 1. A thick-walled tube of stainless steel [18% Cr, 8% Ni, k = 19 W/m C] with 2-cm inner diameter (ID) and 4-cm outer diameter (OD) is covered with a 3-cm layer of asbestos insulation (k = 0.2 W/m. C). If the inside wall temperature of the pipe is maintained at 600C, calculate the heat loss per meter length. Also calculate the tube insulation interface temperature. = m.C 59600 Stainless steel T-600C Asbestos T-100C = 2. A steel pipe with 5-cm OD is covered with a 6.4-mm asbestos insulation [k = 0.096 Btu/h ft. F] followed by a 2.5-cm layer of fiberglass insulation [k = 0.028 Btu/h ft F]. The pipe-wall temperature is 315-C, and the outside insulation temperature is 38-C. Calculate the interface temperature between the asbestos and fiberglass. 3. Suppose a 3-in schedule 80 pipe (d, 2.9 in, do = 3.5 in, k = 43) is covered with 1 in of an insulation having k- 60 pr W/m C and the outside of the insulation is exposed to an environment haying h=10 W/m. C and Too=20-C. The temperature of the inside of the pipe is 250C. For unit length of the pipe calculate (a) overall thermal resistance and (b) heat loss. 4. Two long cylinders 8.0 and 3.0 cm in diameter are completely surrounded by a medium with k = 1.4 W/m C. The distance between centers is 10 cm, and the cylinders are maintained at 200C and 35C. Calculate the heat transfer rate per unit length. 5. Find u(x, y) (assume 2D heat transfer, steady state). . 2 0 TEX sin 0 2 sin vin u(x,y) un ha 0